CN118221062A - Cantilever beam structure with middle substrate connection and device thereof - Google Patents

Abstract

The invention provides a cantilever beam structure and a device thereof. The cantilever structure includes an anchor portion and a membrane structure. The membrane structure covers the cavity and vibrates within the cavity, and the length of the membrane structure is less than the width of the membrane structure. The anchoring portion includes at least one protrusion protruding toward the cavity, and the membrane structure is anchored to the anchoring portion with the protrusion.

Description

Cantilever beam structure with middle substrate connection and device thereof

Technical Field

The present invention relates to a cantilever structure and an apparatus, and more particularly, to a cantilever structure having characteristics that have little variation in manufacturing errors caused by a manufacturing process, and to an associated apparatus.

Background

Cantilever structures are widely used in a variety of electronic components, such as acoustic components, air pulse generating components, sensors, oscillators (oscillators), or other suitable components. In some cases, since the cantilever structure may be a Micro Electro-mechanical system (Micro Electro MECHANICAL SYSTEM, MEMS) structure to have a small size, the size of an electronic component including the cantilever structure may be significantly reduced, thereby being widely used in various electronic devices.

However, some characteristics (e.g., resonant frequency, stiffness, and initial deflection) in the cantilever structure may change due to manufacturing errors caused by the manufacturing process. If the characteristics are changed too much, the performance of the cantilever structure is reduced due to the fact that the characteristics are too different from the design values. Accordingly, there is a need for structural improvements in cantilever structures to reduce the variation in characteristics due to manufacturing errors.

Disclosure of Invention

It is therefore a primary object of the present invention to provide a cantilever structure in which the anchoring portion of the cantilever structure has at least one protrusion to provide some characteristics (e.g., resonant frequency, stiffness and initial deflection) in the cantilever structure with small variations in manufacturing tolerances. The invention also provides a related device.

An embodiment of the present invention provides a cantilever structure that includes an anchor portion and a membrane structure. The membrane structure covers the cavity and vibrates within the cavity, and the length of the membrane structure is less than the width of the membrane structure. The anchoring portion includes at least one protrusion protruding toward the cavity, and the membrane structure is anchored to the anchoring portion with the protrusion.

Another embodiment of the present invention provides an apparatus that includes a first cantilever structure and a second cantilever structure. The first cantilever structure includes a first membrane structure anchored to the anchor portion. The second cantilever structure includes a second membrane structure anchored to the anchor portion. The cavity is formed in the device, and the first membrane structure and the second membrane structure cover the cavity and vibrate in the cavity. The length of the first film structure is smaller than the width of the first film structure, and the length of the second film structure is smaller than the width of the second film structure. The anchor portion includes a plurality of protrusions protruding toward the cavity, the first membrane structure and the second membrane structure being anchored to the anchor portion having the protrusions. The first film structure and the second film structure are adjacent to each other and opposite to each other.

The objects of the present invention will be apparent to those skilled in the art after reading the following detailed description of the embodiments in which various drawings are shown.

Drawings

Fig. 1 and fig. 2 are schematic views of a cantilever structure according to a first embodiment of the present invention.

Fig. 3 is a schematic cross-sectional view of the structure along section line A-A' of fig. 1.

Fig. 4 is a schematic cross-sectional view of the structure along section line B-B' of fig. 1.

Fig. 5 is a schematic view of a cantilever structure according to a second embodiment of the present invention.

Fig. 6 is a schematic view of an apparatus according to an embodiment of the invention.

Fig. 7 is a schematic top view of the device shown in fig. 6.

Fig. 8 is a schematic bottom view of the device shown in fig. 6.

Fig. 9 is a schematic view of the device shown in fig. 6.

The reference numerals are as follows:

60 device

62A,62b,100,200 cantilever beam structure

64A,64b,110 membrane structure

110A anchoring side

112 Sub-section

120 Anchoring portion

120A anchoring edge

122 Block-shaped part

124 Protrusion

124A first portion

124B second portion

124P extending portion

BK block structure

CV cavity

FL film layer

Length L

SB base plate

SL slit

SL1 external slit

SL2 inner slit

SL3 split slit

T1 first thickness

T2 second thickness

W is width

X, Y, Z direction

Detailed Description

In order to enable those skilled in the art to make a further understanding of the invention, preferred embodiments of the invention, exemplary materials or parameters of the key elements will be described in detail below, together with the accompanying drawings with which the numerals are used to describe the elements of the invention and the desired effects. It is noted that the drawings are simplified schematic representations showing the materials and parameters of the key elements based on the prior art, and therefore show only the elements and combinations related to the present invention to provide a clearer description of the basic construction, method of implementation or operation of the present invention. The actual components and layout may be more complex and the materials or parameters used may vary with future technology. In addition, for convenience of explanation, elements shown in the drawings of the present invention may not be drawn in the actual number, shape, size, etc. and the details thereof may be adjusted according to the design requirements.

In the following description and claims, the terms "include," have, "and the like are open-ended terms, and thus should be interpreted to mean" include, but not limited to …. Thus, when the terms "comprises," "comprising," and/or "having" are used in the description of the present invention, they specify the presence of the corresponding features, regions, steps, operations, and/or components, but do not exclude the presence of one or more corresponding features, regions, steps, operations, and/or components.

In the following description and claims, when "A1 member is formed of B1," B1 is present in the formation of A1 member or B1 is used in the formation of A1 member, and the formation of A1 member does not preclude the presence or use of one or more other features, regions, steps, operations and/or members.

In the following description and claims, the term "substantially" refers to the presence or absence of minor deviations. For example, the terms "substantially parallel" and "substantially along" refer to an included angle between two members that may be less than or equal to a particular angle threshold, such as 10 degrees, 5 degrees, 3 degrees, or 1 degree. For example, the term "substantially aligned" means that the deviation between the two members may be less than or equal to a particular variance threshold, such as 2 μm (micrometers) or 1 μm. For example, the term "substantially identical" means that the deviation is within a given value or range, such as within 10%, 5%, 3%, 2%, 1%, or 0.5%.

In the following description and claims, the term "horizontal direction" means a direction parallel to a horizontal plane, the term "horizontal plane" means a plane parallel to the directions X and Y in the drawing (i.e., the directions X and Y of the present invention may be regarded as horizontal directions), and the term "vertical direction" means a direction parallel to the direction Z and perpendicular to the horizontal direction in the drawing, wherein the directions X, Y, Z are perpendicular to each other. In the following description and claims, the term "top view" means a view along a vertical direction, and the term "bottom view" means a view along another vertical direction, which is opposite to the vertical direction with respect to the top view. In the following description and claims, the term "section" is the viewing result of a structure cut along the vertical direction and viewed from the horizontal direction.

As used in this specification and in the claims, the terms "first," "second," and the like, are used to modify an element, which itself cannot be represented by any preceding ordinal number, nor does it represent the order in which one element is joined to another element, or the order in which the elements are fabricated, but rather the use of multiple ordinal numbers is merely used to make the element having a certain name clearly distinguishable from another element having the same name. The same words may not be used in the claims and the specification, whereby a first element in the description may be a second element in the claims.

It is to be understood that the following exemplary embodiments may be substituted, rearranged, and mixed for the features of several different embodiments without departing from the spirit of the invention to accomplish other embodiments. Features of the embodiments can be mixed and matched at will without departing from the spirit of the invention or conflicting.

A cantilever structure is provided in the present invention, wherein the cantilever structure may be used on any suitable element.

In some embodiments, the cantilever structure may be applied to acoustic elements associated with acoustic waves (e.g., acoustic and/or ultrasonic waves). In some cases, the cantilever structure of the acoustic element may be directly related to the acoustic wave. For example, the acoustic element (or cantilever structure) may generate or receive acoustic waves, or the acoustic element may be a path through which acoustic waves pass. For example, the acoustic element (or cantilever structure) may enhance the user's experience of using an acoustic device with the acoustic element.

The acoustic elements (or cantilever structures) may be controlled by signals, or may generate signals from acoustic waves, where the signals may be electrical signals or other suitable types of signals.

In some embodiments, the acoustic element may be an acoustic transducer (acoustic transducer) to perform acoustic conversion (acoustic transformation) (e.g., a cantilever structure performs acoustic conversion), where the acoustic conversion may convert a signal (e.g., an electrical signal) to an acoustic wave, or may convert an acoustic wave to another suitable type of signal (e.g., an electrical signal), but is not limited thereto. For example, the acoustic transducer may be a sound generating element, a speaker, a micro-speaker, or other suitable device to convert an electrical signal into an acoustic wave, but is not limited thereto. For example, the acoustic transducer may be a sound measurement device, a sound pressure sensing device, a microphone or other suitable device to convert acoustic waves into electrical signals, but is not limited thereto.

In some embodiments, the acoustic element may be a vent element in an acoustic device, and the size of the vent opening of the vent element may be controlled by an electrical signal (e.g., the vent opening is caused by a cantilever structure). For example, the venting element may be used to inhibit a latch-up effect (occlose effect) during operation of an acoustic device, such as an in-ear earphone (or earplug earphone), an over-the-ear earphone (on-ear earphone), or an over-the-ear earphone (ear earphone), etc. The occlusion effect is due to the sealed volume of the ear canal to cause a large perceived sound pressure by the user (i.e., listener). In some cases, when a user performs a specific motion (e.g., walking, running, speaking, chewing, touching an acoustic transducer, etc.) using an acoustic device inserted into the ear canal to generate bone conduction sound, a lock-out effect occurs, which causes the user to hear a lock-out noise (occlusion noise), thereby reducing the user's listening quality. Therefore, when the ventilation opening of the ventilation element is opened, the volume in the auditory canal is not sealed based on the existence of the ventilation element, so as to inhibit the locking effect, thereby improving the performance of the acoustic device and the experience of a user using the acoustic device.

In some embodiments, the cantilever structure may be a MEMS structure in a MEMS element, but is not limited thereto. Also, in some embodiments, the acoustic elements including the cantilever structures may be MEMS elements, but are not limited thereto. In other words, the elements (e.g., acoustic transducers, venting elements, or any other suitable and acoustic-related element) may be formed by a semiconductor process such that the microstructure of the elements may be, but is not limited to, MEMS structures.

In some embodiments, the cantilever structure may be encapsulated in a package structure. Therefore, the acoustic element including the cantilever structure may be a package structure, but is not limited thereto.

Hereinafter, for example, the cantilever structure may generate an acoustic wave such that the acoustic element comprising the cantilever structure may be an acoustic transducer to generate the acoustic wave, and the cantilever structure may be a MEMS structure in the MEMS element, but is not limited thereto.

Referring to fig. 1 to 4, fig. 1 and 2 are schematic diagrams of a cantilever structure according to a first embodiment of the present invention, fig. 3 is a cross-sectional view of the structure along a section line A-A 'of fig. 1, and fig. 4 is a cross-sectional view of the structure along a section line B-B' of fig. 1. As shown in fig. 1-4, the cantilever structure 100 may include a substrate SB, wherein the substrate SB may comprise any suitable material as desired. In some embodiments, since the cantilever structure 100 may be a MEMS structure in a MEMS element (e.g., a MEMS chip), the material of the substrate SB may be formed and/or etched by a semiconductor process. In this case, the substrate SB may include silicon (e.g., single crystal silicon or polycrystalline silicon), a silicon compound (e.g., silicon carbide, silicon oxide), germanium (germanium), a germanium compound, gallium (gallium), a gallium compound (e.g., gallium nitride, gallium arsenide), other suitable materials, or combinations thereof, for example. Note that, the normal direction of the substrate SB may be parallel to the direction Z.

As shown in fig. 1 to 4, the substrate SB is etched to form a cavity CV within the substrate SB (i.e., the cavity CV is formed within the cantilever structure 100), and a thin film layer FL and a bulk structure BK included within the substrate SB may be formed accordingly, wherein the thin film layer FL covers the cavity CV (i.e., the thin film layer FL corresponds to and overlaps the cavity CV in the direction Z), the bulk structure BK is disposed outside the thin film layer FL and directly connects the thin film layer FL, and a first thickness T1 of the bulk structure BK is greater than a second thickness T2 of the thin film layer FL. For example, in fig. 1, the film layer FL and the cavity CV may be surrounded by a block-shaped structure BK, but not limited thereto. It should be noted that, the thin film layer FL corresponds to the removed portion of the substrate SB in the direction Z, and the block-shaped structure BK is an unetched portion of the substrate SB.

In another aspect, as shown in fig. 1 to 4, after forming the cavity CV, the film structure 110 and the anchor portion 120 included in the substrate SB may be formed accordingly, wherein the film structure 110 is anchored on the anchor portion 120 and covers the cavity CV (i.e., the film structure 110 corresponds to and overlaps the cavity CV in the direction Z), and the anchor portion 120 is disposed outside the film structure 110. For example, in fig. 1, the membrane structure 110 may be surrounded by the anchor portion 120, but is not limited thereto.

In fig. 1 to 4, the film structure 110 and a part of the anchor portion 120 belong to the thin film layer FL (i.e., the film structure 110 and a part of the anchor portion 120 are formed in the thin film layer FL), and the other part of the anchor portion 120 belongs to the block structure BK. Note that, since the anchor portion 120 has a part belonging to the thin film layer FL and another part belonging to the block structure BK, the anchor portion 120 has two different thicknesses.

In operation of the cantilever structure 100, the membrane structure 110 may be actuated to move and vibrate within the cavity CV and the anchor 120 may be stationary. In other words, during operation of the cantilever structure 100, the anchor portion 120 may be a fixed end (or fixed edge) relative to the membrane structure 110. In some embodiments, the membrane structure 110 may be actuated to move up and down, but is not limited thereto. In the present invention, the terms "upward movement" and "downward movement" mean that the membrane structure 110 moves substantially along the direction Z.

In fig. 1, the membrane structure 110 has only one anchoring side 110a to anchor it to the anchoring portion 120, with the other side of the membrane structure 110 being the non-anchoring side. In other words, the membrane structure 110 may be a cantilever beam.

In fig. 1, the anchoring portion 120 includes an anchoring edge 120a, and the anchoring side 110a of the membrane structure 110 is anchored to the anchoring edge 120a of the anchoring portion 120, such that the membrane structure 110 is anchored to the anchoring portion 120. In fig. 1, an anchor edge 120a of the anchor portion 120 is an edge of the block structure BK. In other words, the anchoring edge 120a of the anchoring portion 120 is a boundary of the block-shaped structure BK having the first thickness T1.

As shown in fig. 1 to 4, the anchoring portion 120 includes a block 122 and at least one protrusion 124, the protrusion 124 protrudes from the block 122 toward the cavity CV, and the block 122 has a first thickness T1 belonging to the block structure BK. Each protrusion 124 includes a first portion 124a and a second portion 124b directly connected to each other, wherein the first portion 124a belongs to the bulk structure BK and has substantially a first thickness T1, and the second portion 124b belongs to the thin film layer FL and has substantially a second thickness T2 smaller than the first thickness T1 (i.e., in the thin film layer FL, the second portion 124b has substantially the same thickness as the film structure 110). It should be noted that, the anchoring edge 120a of the anchoring portion 120 (the anchoring edge 120a is the boundary of the block structure BK) is an edge having at least one protrusion due to the presence of the at least one protrusion 124 (i.e., the anchoring edge 120a of the anchoring portion 120 is formed by the block 122 and the first portion 124a of the protrusion 124).

As shown in fig. 1-4, the first portion 124a of the protrusion 124 is between the second portion 124b of the protrusion 124 and the block portion 122, and the second portion 124b of the protrusion 124 is between the first portion 124a of the protrusion 124 and the membrane structure 110. As shown in fig. 1 and 4, the membrane structure 110 is directly connected (anchored) to the block portion 122 and the first portion 124a of the protrusion 124, and the membrane structure 110 and the second portion 124b of the protrusion 124 are separated from each other such that the membrane structure 110 is not directly connected (not anchored) to the second portion 124b of the protrusion 124. In some embodiments, as shown in fig. 1, the first portion 124a may extend into the second portion 124b in a top view, wherein the extending portion 124p extending into the second portion 124b in the first portion 124a may not be directly connected to the film structure 110, but is not limited thereto.

It should be noted that the protrusion 124 serves as an intermediate substrate connection (INTERMEDIATE SUBSTRATE CONNECTION) and also provides an anchoring function such that the distance between the cantilever Liang Jianduan to the anchor in the width direction is more uniform than would be the case without the protrusion 124 (i.e., intermediate substrate connection).

The shape of the protrusion 124 and the shape of the block 122 can be designed according to the requirements. The shape of the block 122 may be a suitable shape having a suitable recess forming the cavity CV, wherein this suitable shape may be polygonal (e.g., rectangular), a shape having curved edges (e.g., circular, oval), or other suitable shape. The shape of the first portion 124a and the shape of the second portion 124b of the protrusion 124 may each be polygonal (e.g., rectangular), have curved edges (e.g., circular, oval), or other suitable shapes. For example, in fig. 1, the block 122 may be rectangular with a rectangular recess, the first portion 124a of the protrusion 124 may be rectangular, and the combination of the second portion 124b of the protrusion 124 and the protruding portion 124p of the first portion 124a may be a shape with two opposite straight edges and two opposite curved edges, but is not limited thereto.

In the present invention, the number of the protrusions 124 can be designed according to the need. In fig. 1 and 2, the anchoring portion 120 includes a plurality of protrusions 124, and the arrangement of the protrusions 124 can be designed according to the requirements. For example, in fig. 1 and 2, the anchoring portion 120 includes seven protrusions 124, and the seven protrusions 124 are uniformly distributed on the anchoring side 110a (the anchoring edge 120a of the anchoring portion 120) of the membrane structure 110, but not limited thereto.

In order to form the foregoing design of the film structure 110, the cantilever structure 100 includes at least one slit SL formed on and through the film layer FL to define the film structure 110 and the second portion 124b of the protrusion 124. In the present invention, the number of the slits SL can be adjusted according to the requirement, and the slits SL can be arranged at any suitable position in the film layer FL and have any suitable top view pattern. For example, the slit SL may be a straight slit, a curved slit, a combination of straight slits, a combination of curved slits, or a combination of straight slits and curved slits. For example, in the present embodiment, the cantilever structure 100 may include a plurality of slits SL formed on the thin film layer FL.

In fig. 1, 3 and 4, the slit SL includes a plurality of outer slits SL1, and the outer slits SL1 surround the membrane structure 110 such that the membrane structure 110 and the anchor portion 120 are separated from each other at the non-anchor side. In fig. 1, the film structure 110 is formed due to the presence of the outer slit SL 1. For example, in fig. 1, three outer slits SL1 are formed to surround the film structure 110, and each outer slit SL1 is a linear slit, but not limited thereto.

In fig. 1 and 4, the slit SL includes a plurality of inner slits SL2, wherein each inner slit SL2 is between the second portion 124b of the protrusion 124 and the film structure 110 such that the film structure 110 and the second portion 124b of the protrusion 124 are separated from each other by the inner slit SL 2. In fig. 1, the second portion 124b of the protrusion 124 is formed due to the presence of the inner slit SL2, and one inner slit SL2 corresponds to the second portion 124b of one protrusion 124. For example, in fig. 1, seven inner slits SL2 are formed on and through the film layer FL, and each inner slit SL2 is a combination of a straight slit and a curved slit. For example, in fig. 1, two outer slits SL1 are each connected to a different inner slit SL2, but not limited thereto.

According to the foregoing arrangement, in fig. 1, the film structure 110 may include a plurality of sub-portions 112, such sub-portions 112 being distinguished by protrusions 124 (in fig. 1, the film structure 110 includes six sub-portions 112), such that one protrusion 124 and one inner slit SL2 are between two adjacent sub-portions 112. In fig. 1, the sub-portions 112 are connected to each other (i.e., the sub-portions 112 are not separated from each other).

In the present invention, the dimensions of the membrane structure 110 may be designed according to the requirements. In some embodiments, in fig. 1, the length L of the film structure 110 in the direction Y may be less than the width W of the film structure 110 in the direction X to maximize the utilization of MEMS elements (e.g., MEMS chips) used to form the cantilever structure 100 and formed by a semiconductor process. For example, the width W of the film structure 110 is greater than 2 times the length L of the film structure 110, but is not limited thereto. It should be noted that, the length L of the membrane structure 110 is the maximum distance between the anchoring side 110a of the membrane structure 110 (or the anchoring edge 120a of the anchoring portion 120) and the free side of the membrane structure 110 in the direction Y (i.e., the distance between the anchoring end and the free end of the cantilever beam), and the width W of the membrane structure 110 is the dimension of the membrane structure 110 in the direction perpendicular to the length L.

With respect to the membrane structure 110 (i.e., cantilever beam), the resonant frequency, stiffness, and initial deflection of the membrane structure 110 are related to the length L (length of the cantilever beam) of the membrane structure 110. For example, the resonant frequency of the membrane structure 110 is proportional to the length L of the membrane structure 110, and the stiffness of the membrane structure 110 is proportional to the third power of the length L of the membrane structure 110. In general, the length L of the film structure 110 may be changed due to manufacturing errors (e.g., mask errors, alignment errors, etching errors, other errors, or combinations thereof) caused by the manufacturing process, such that the resonant frequency, stiffness, and initial deflection of the film structure 110 may be changed due to the manufacturing errors. In addition, if the length L of the membrane structure 110 is smaller than the width W of the membrane structure 110, the changes in the resonant frequency, stiffness and initial deflection of the membrane structure 110 are more affected by the changes in the length L of the membrane structure 110.

In the present invention, since the membrane structure 110 is divided into the plurality of sub-portions 112 due to the presence of the protrusions 124 of the anchor portion 120, when the length L of the membrane structure 110 is changed due to a manufacturing error, the amount of change in the resonance frequency, rigidity, and initial deflection of the membrane structure 110 is reduced. In some cases, the length of the protrusions 124 will correspondingly increase/decrease (i.e., manufacturing errors occur at the anchored side 110a of the membrane structure 110) as the length L of the membrane structure 110 increases/decreases to reduce the amount of change in the resonant frequency, stiffness, and initial deflection of the membrane structure 110 caused by the change in the length L of the membrane structure 110. Also, since the protrusion 124 has the second portion 124b, when manufacturing errors (e.g., dimensional errors and/or offset errors) result in manufacturing errors of the first portion 124a of the protrusion 124, the second portion 124b of the protrusion 124 may act as a buffer zone to reduce the influence of the manufacturing errors on the film structure 110.

In the film structure 110 of the present invention, the first ratio is the rate of change of the resonant frequency of the film structure 110 (Δf/Δl) with respect to the length L of the film structure 110. In a conventional membrane structure without protrusions (i.e., conventional design), the second ratio is the rate of change (Δf '/Δl') of the resonant frequency of this conventional membrane structure for the length of this conventional membrane structure. The first ratio is smaller than the second ratio, for example, but not limited to, the first ratio may be smaller than half the second ratio.

For example, in a comparison between a cantilever structure of an embodiment of the present invention (e.g., the cantilever structure 100 shown in fig. 1-4) and a conventional cantilever structure similar to the cantilever structure of the present invention but without the protrusions 124, the first ratio of the membrane structure 110 of the cantilever structure of the present invention may be 0.79 kilohertz/micrometer (kHz/μm), and the second ratio of the conventional membrane structure of the conventional cantilever structure may be 1.77 kilohertz/micrometer, such that the ratio of the first ratio to the second ratio is 0.446 (i.e., the improvement caused by the protrusions 124 of the present invention may be 55.4%), but is not limited thereto. It should be noted that the first ratio and the second ratio are experimental data, and these ratios are not limitations of the present invention.

Cantilever structure 100 may also include any suitable structure and/or element. In some embodiments, since the acoustic element comprising the cantilever structure may be an acoustic transducer to generate acoustic waves, the cantilever structure 100 comprises an actuator disposed on the membrane structure 110 and configured to actuate the membrane structure 110. For example, the actuating member may be disposed on the membrane structure 110 in the direction Z, but is not limited thereto.

The actuator may have a monotonic electromechanical transduction function for movement of the membrane structure 110 in the direction Z. In some embodiments, the actuator may include, but is not limited to, a piezoelectric actuator, an electrostatic actuator, a nano-electrostatic-driven (NED) actuator, an electromagnetic actuator, or any other suitable actuator. For example, in one embodiment, the actuating element may include a piezoelectric actuating element, which may include, for example, two electrodes and a piezoelectric material layer (e.g., lead zirconate titanate (lead zirconate titanate, PZT)) disposed between the two electrodes, wherein the piezoelectric material layer may actuate the membrane structure 110 according to a driving signal (e.g., a driving voltage and/or a driving voltage difference between the two electrodes) received by the electrodes, but is not limited thereto. For example, in another embodiment, the actuating element may include an electromagnetic actuating element (such as a planar coil), wherein the electromagnetic actuating element may actuate the membrane structure 110 (i.e., the membrane structure 110 may be actuated by electromagnetic force) according to the received driving signal (e.g., driving current) and the magnetic field, but not limited thereto. For example, in another embodiment, the actuating element may include an electrostatic actuating element (e.g., a conductive plate) or a NED actuating element, wherein the electrostatic actuating element or the NED actuating element may actuate the membrane structure 110 (i.e., the membrane structure 110 may be actuated by an electrostatic force) according to the received driving signal (e.g., driving voltage) and the electric field, but is not limited thereto.

The cantilever structure of the present invention is not limited to the above embodiments, and other embodiments will be further disclosed herein, however, for simplicity of description and highlighting the differences between the embodiments and the above embodiments, the same reference numerals are used to designate the same elements, and the overlapping parts will not be repeated.

Referring to fig. 5, fig. 5 is a schematic diagram of a cantilever structure according to a second embodiment of the invention. As shown in fig. 5, the slit SL of the cantilever structure 200 further includes at least one split slit SL3, and the split slit SL3 is between two adjacent sub-portions 112 of the film structure 110 to separate the two adjacent sub-portions 112 of the film structure 110. In fig. 5, one split slit SL3 corresponds to one protrusion 124. For example, one split slit SL3 is connected between one outer slit SL1 and one inner slit SL2 corresponding to the second portion 124b of one protrusion 124.

The number of split slits SL3 can be designed according to the need. For example, the slits SL include five split slits SL3 to separate all the sub-portions 112 (e.g., six sub-portions 112 in fig. 5) of the film structure 110, but not limited thereto.

In fig. 5, the combination of the protruding portion 124p of the first portion 124a and the second portion 124b of the protrusion 124 may have a peach shape, such that the inner slit SL2 may be a combination of curved slits, but is not limited thereto.

It should be noted that the cantilever structure of the present invention can be applied to acoustic transducers and sound generating devices. Specifically, the cantilever structure of the present invention can be applied to the air pulse generating devices disclosed in U.S. patent application Ser. Nos. 17/553,806 and 18/321,759 filed by the applicant. The contents of U.S. patent application Ser. Nos. 17/533,806 and 18/321,759 are incorporated by reference herein and form a part of the present specification.

Referring to fig. 6, fig. 6 is a schematic diagram of an apparatus according to an embodiment of the invention. The device 60 may be a sound emitting device or an air pulse generating device, which may be a sound emitting device or an air pulse generating device as disclosed in U.S. patent application Ser. No. 18/321,759, incorporating the intermediate substrate connection (protrusion 124) described herein. That is, the device 60 differs from the device disclosed in U.S. patent application Ser. No. 18/321,759 by the protrusion 124 (intermediate substrate connection).

As shown in fig. 6, the device 60 includes cantilever structures 62a, 62b. The cantilever structures 62a, 62b may have structures similar or identical to the cantilever structures shown in fig. 5, while different views of the cantilever structures 62a, 62b are illustrated in fig. 7-9. The cantilever structures 62a, 62b include membrane structures 64a, 64b, respectively, the membrane structures 64a, 64b being opposite each other and separated by an outer slit SL 1. The membrane structures 64a, 64b of the present invention may be considered flaps (flaps) of U.S. patent application Ser. No. 18/321,759.

The principle of operation of the device 60 may be found in U.S. patent application Ser. Nos. 17/533,806, 18/321,759. As taught in U.S. patent application Ser. Nos. 17/533,806, 18/321,759, the membrane structure within the device 60 generates an amplitude modulated ultrasonic air wave (amplitude-modulated ultrasonic air wave) (or amplitude modulated ultrasonic air pressure variation (amplitude-modulated ultrasonic air pressure variation)) having an ultrasonic carrier frequency and forms an opening at a switching frequency synchronized with the ultrasonic carrier frequency. The apparatus 60 generates a plurality of air pulses at a pulse frequency of the ultrasonic carrier frequency in accordance with the amplitude modulated ultrasonic air pressure variation. It should be noted that the membrane structures 64a, 64b may be fabricated in a single membrane layer.

Furthermore, as taught in U.S. patent application Ser. No. 18/321,759, the membrane structures 64a, 64b are fabricated in a single membrane layer, the membrane structures 64a, 64b being actuated to perform both common mode motion (common mode movement) and differential mode motion (DIFFERENTIAL MODE MOVEMENT). The membrane structures 64a, 64b perform a common mode motion to form amplitude modulated ultrasonic air pressure variations having an ultrasonic carrier frequency, while the membrane structures 64a, 64b perform a differential mode motion to form openings at a switching frequency synchronized with the ultrasonic carrier frequency.

For details of the principle of operation, reference is made to U.S. patent application Ser. Nos. 17/533,806 and 18/321,759, which are not repeated here for the sake of brevity.

In the present invention, the MEMS element having a function different from that of the acoustic element may also have the cantilever structure of one of the foregoing embodiments or the cantilever structure combined with the foregoing embodiments. In some embodiments, the MEMS element may be an oscillator, a thermal energy converter, an optical converter, an inertial converter, a filter, a radio-frequency (RF) MEMS element, a switching element, or other suitable MEMS element.

In summary, according to the design of the present invention, when the length of the membrane structure is changed due to manufacturing errors, the amount of variation of some characteristics (e.g., resonance frequency, stiffness, and initial deflection) of the membrane structure is reduced.

The foregoing description is only of the preferred embodiments of the invention, and all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (21)

1. A cantilever structure comprising:

An anchor portion; and

A membrane structure;

wherein the membrane structure covers a cavity and vibrates within the cavity;

wherein the length of the film structure is less than the width of the film structure;

wherein the anchoring portion includes at least one protrusion protruding toward the cavity, the membrane structure being anchored to the anchoring portion having the at least one protrusion.

2. The cantilever structure of claim 1, further comprising a substrate, wherein the cavity is formed in the substrate.

3. The cantilever structure of claim 2, wherein the substrate is etched to form the cavity and the anchor portion with the at least one protrusion.

4. The cantilever structure of claim 1,

Wherein the membrane structure is formed in a thin film layer;

Wherein at least one slit is formed on the thin film layer to surround the film structure.

5. The cantilever structure of claim 1, wherein the at least one protrusion of the anchor portion is a plurality of protrusions.

6. The cantilever structure of claim 5,

Wherein the membrane structure comprises an anchoring side anchored to the anchoring portion;

Wherein the plurality of protrusions are evenly distributed on the anchoring side.

7. The cantilever structure of claim 1, wherein the width of the membrane structure is greater than 2 times the length of the membrane structure.

8. The cantilever structure of claim 1, wherein each of the at least one protrusion comprises a first portion and a second portion, a first thickness of the first portion being greater than a second thickness of the second portion.

9. The cantilever structure of claim 8, wherein the membrane structure is directly connected to the first portion, the membrane structure not being directly connected to the second portion.

10. The cantilever structure of claim 8, wherein the membrane structure and the second portion are separated from each other by an internal slit between the second portion and the membrane structure.

11. The cantilever structure of claim 8, wherein the second portion is between the first portion and the membrane structure.

12. The cantilever structure of claim 8, wherein the anchor portion includes a block portion from which the at least one protrusion protrudes toward the cavity, the first portion being between the second portion and the block portion.

13. The cantilever structure of claim 8, wherein the first portion extends into the second portion in a top view.

14. The cantilever structure of claim 8, wherein the second thickness of the second portion is the same as the thickness of the membrane structure.

15. The cantilever structure of claim 8, wherein the second portion and the membrane structure are formed in a thin film layer, an internal slit being formed on the thin film layer between the second portion and the membrane structure.

16. The cantilever structure of claim 1, wherein the membrane structure comprises a plurality of sub-portions, one of the at least one protrusion being between adjacent two of the plurality of sub-portions.

17. The cantilever structure of claim 1, wherein the membrane structure comprises a plurality of sub-portions, a slit between adjacent two of the plurality of sub-portions, the slit corresponding to one of the at least one protrusion.

18. An apparatus, comprising:

a first cantilever structure comprising a first membrane structure, said first membrane structure being anchored to an anchor portion; and

A second cantilever structure comprising a second membrane structure, said second membrane structure being anchored to said anchor portion;

wherein a cavity is formed within the device;

Wherein the first membrane structure and the second membrane structure cover the cavity and vibrate within the cavity;

wherein the length of the first film structure is less than the width of the first film structure and the length of the second film structure is less than the width of the second film structure;

Wherein the anchoring portion comprises a plurality of protrusions protruding toward the cavity, the first and second membrane structures being anchored on the anchoring portion having the plurality of protrusions;

Wherein the first and second film structures are adjacent to and opposite each other.

19. The apparatus of claim 18,

Wherein the device generates an amplitude modulated ultrasonic air pressure variation having an ultrasonic carrier frequency and forms an opening at a switching frequency synchronized with the ultrasonic carrier frequency;

wherein the device generates a plurality of air pulses at a pulse frequency of the ultrasonic carrier frequency in accordance with the amplitude modulated ultrasonic air pressure variation.

20. The apparatus of claim 19,

Wherein the first membrane structure and the second membrane structure are actuated to perform a common mode motion and a differential mode motion;

Wherein the common mode motion is creating the amplitude modulated ultrasonic air pressure variation having the ultrasonic carrier frequency;

Wherein the differential mode motion is to form the aperture at the switching frequency synchronized with the ultrasonic carrier frequency.

21. The device of claim 18, wherein the device is an air pulse generating device.